MSE Faculty Candidate Seminar: “Atom-Scale Engineering using 2D Materials”

Materials engineered with atomic precision promise unprecedented control over their structure and properties, with profound implications for enhancing electronic devices and enabling quantum technologies. Atomically thin two-dimensional (2D) materials provide a versatile platform for atom-scale engineering: they exhibit a variety of superlative electronic characteristics, and their discrete layered structures and van der Waals (vdW) bonding enable them to be grown, patterned, and stacked to generate heterostructured solids with atomic-scale control. In this talk, I will discuss two key steps towards realizing atom-scale engineering with 2D materials: the growth of synthetic 2D materials and the automated fabrication of patterned vdW heterostructures.

To date, the study of 2D materials has focused on structures derived from layered vdW solids (e.g., graphene from graphite). However, the growth of entirely synthetic 2D materials—those without bulk analogues—dramatically expands the phase space for new structures with novel properties. To illustrate this point, I will present the synthesis of 2D boron sheets (i.e., borophene), which were grown on a silver surface under ultra-high vacuum conditions. I will show that borophene exhibits unique ordered-vacancy atomic structures which are metallic (unlike the semiconducting bulk) and distinct from all known bulk boron allotropes. This approach can be generalized to explore elemental and compound 2D structures which cannot be realized in layered crystals.

This concept can be extended to the construction of synthetic vdW solids formed by stacking different 2D materials, resulting in functionality embedded in the atom-scale order of the material. Toward this end, I will discuss the automated microfabrication of stacked 2D heterostructures under vacuum conditions. I will conclude with an outlook for further prospects of atom-scale engineering with 2D materials and their potential for future quantum technologies.

***

Andrew J. Mannix earned his B.S. in Materials Science and Engineering at the University of Illinois at Urbana-Champaign and his Ph.D. in Materials Science and Engineering at Northwestern University. His graduate work explored the growth and atomic-scale characterization of synthetic 2D materials. He is currently a Kadanoff-Rice Postdoctoral Fellow in the James Franck Institute at the University of Chicago, where he works on new methods of atomically-thin nanomaterials growth, processing, and assembly.